<template>
  <div class="nav-bar" :class="{'is_fixed':isFixed}">
    <div class="container" >
      <div class="pro-title">
        {{title}}
      </div>
      <div class="pro-param">
        <a href="javascript:;">概述</a><span>|</span>
        <a href="javascript:;">参数</a><span>|</span>
        <a href="javascript:;">用户评价</a>
        <slot name="buy"></slot>
      </div>
    </div>
  </div>
</template>

<script>
  
  export default {
    name:'nav-bar',
    props:{
      title:String
    },
    data() {
      return {
        isFixed:false,

      }
    },
    mounted () {
      window.addEventListener('scroll',this.initHeight)
    },
   methods: {
     initHeight() {
       let scrollTop = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop 
       
       this.isFixed = scrollTop > 152 ? true : false;
       
     }
   },
   destroyed () {
     window.removeEventListener('scroll',this.initHeight,false)
   },
  }
</script>

<style lang="scss">
@import './../assets/scss/config.scss';
@import './../assets/scss/mixin.scss';
.nav-bar{
  height: 70px;
  line-height: 70px;
  border-top: 1px solid $colorH;
  background-color: $colorG;
  box-shadow: 0 5px 5px $colorE;
  z-index: 10;
  &.is_fixed{
    position: fixed;
    top:0;
    width: 100%;
  }
  .container{
    @include flex();
    .pro-title{
      font-size: $fontH;
      color: $colorB;
      font-weight: bold;
    }
    .pro-param{
      font-size: $fontJ;
      span{
        margin: 0 10px;
      }
      a{

        color: $colorC;
        
      }

    }
  }
}
</style>